Swiftkey: Can't get it to load/work

Swiftkey: Can't get it to load/work

I had it working when I first got the phone a 5 days ago, but as of 3 days ago it hasn't worked at all. I see it enable in the "Language and Input" settings, but it doesn't show up when I try to use a keyboard in Gmail or texting. Am I missing something, or is it some bug?

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